EP 1 161 857 A describes a picker for the harvesting of stalk-like plants that includes a conveying element rotating about a vertical axis with drivers extending outward. The drivers grasp the plants standing on the fields and transport them in the sideways direction and to the rear, so that they reach a plucking slot. The plants are transported through the picking gap by means of two picking rolls arranged underneath the picking gap in interaction with the drivers of the conveying element. A further screw conveyor is arranged above the picking slot on the side of the picking gap opposite the conveying element, in order to simplify the introduction of the plants into the picking gap.
In the implement described there is equipped with an operating width considerably greater than that of conventional pickers that operate with gathering chains. It was therefore even considered that this implement could be used for the harvest of corn that is planted in so-called equal spaced or close spaced sowing. In equal spaced sowing, plants are planted with row spacing of 30 cm. The plants of adjoining rows are offset uniformly from each other and the spacing of the plants in a row equals 33.3 cm. The result is a hexagonal pattern with 10 plants per square meter and with equal spacing between all plants, which enhances the growth of the plants. When such a stand is harvested the result is a rather small spacing of rows, in which the dimensioning of the stalk dividers that precede the picking units becomes critical. If the stalk dividers are selected too narrow, they cannot move the plants to the side in order to conduct them to the conveying element; if, on the other hand, they are selected too wide, they can bend over the plants and shake the cobs down off the plants. Such losses are undesirable.
EP 0 780 050 A describes a harvesting implement of this class for plants planted in rows, in which a knife beam is preceded by a multitude of stalk dividers arranged to the side alongside each other. Each of the stalk dividers includes a point that is supported through a pivot bearing with a horizontal pivot axis extending transverse to the forward direction on the frame of the harvesting implement. Thereby a runner attached underneath the point can conform to varying terrain conditions in that it moves downward or upward. The aforementioned problem cannot be solved by these stalk dividers.
DE 73 42 482 U describes a one-piece front attachment corn picker in which the outer divider points can be slid in the sideways direction between a transport position and an operating position. EP 1 179 292 A describes another front harvesting attachment in which the outermost divider points are pivoted to the outside in the transport position, in order to avoid collisions between these divider points above the main frame. These two publications describe divider points that are rigidly attached to the harvesting implement during the harvesting operation and are moved in the sideways direction only during the transition from the transport position to the operating position and the reverse, and hence cannot solve the aforementioned problem.